Reverse lights not working

[firejeep]

CJ7 1978. New wiring harness throughout. Reverse light worked, then stopped working about a year later. I have replaced the switch, and the lights, I have power to the switch and when I depress the switch one of the terminal does not have power. The Transmission has the rod inside to depress switch.
Any ideas ?

Thanks

PS tried to find other threads but no help

Does the engine have to be running or just the key on ??

 

[HackFabrication]

So....

With the key 'on', and the Transmission in reverse, do you have power going to the back up lights? If yes, you have either burnt out bulbs, or a bad ground. Most likely a bad ground.

If you have no power going into or out of the switch, you might have a blown fuse.

 

[BusaDave9]

When the key is turned to ON the Transmission switch should have voltage to one terminal all the time. When you shift into reverse the 2nd terminal should get voltage. If the voltage on both terminals drops when you shift into revers it sounds like you have a short. Do you have a blown fuse?
The most likely place a short would be is the light sockets for the backup lights. With the key off and the Transmission NOT in reverse remove both backup bulbs. Check the resistance from the center electrode in the light socket to ground.

You should not get a reading even with your ohm meter set to mega-ohms. If you do get a reading you have a short.

 

[firejeep]

Hack, I did not check power at the rear light socket. I will check that tomorrow.
It has new bulbs.
Thanks will let you know tomorrow what happens

 

[firejeep]

Busa, In reverse I have power to both sides of the switch with it connected but not installed, to check power. I pushed on the ball and then had power to one side. ( key on ).
I will have to check the light sockets tomorrow. I will let you know what happens, thanks. Fuses are all good.

 

[firejeep]

Busa,
Thanks for the picture.

 

[firejeep]

OK i got no reading on meter. All wires intact, not sure what to check next.
Thanks

 

[wm69]

If you have power to one side of switch, and push the ball, you should have power coming out of the other side of the switch.

Sounds to me like you have an issue with a bad switch or something internal on the Transmission .

First thing to do would be to check power going to switch, and with it in your hand, then push the ball and see if when you do that you get power coming out of switch. If you don't, it's a bad switch.

 

[Lumpy Grits]

When you push the ball all the way in on the r'switch.
You should have continuity with the switch's leads.
Replace the switch--They do 'die'.
Buy a spare too.
LG

 

[firejeep]

OK I have continuity to both sides of switch, push the ball in and only one side has it.

 

[Lumpy Grits]

You should only see continuity across the 2 terminals, when you push down on the ball.
Your switch is dead--
LG

 

[firejeep]

Just to be clear, the plug has power on one side. When I plug the switch in holding in hand, I have power to both sides. Push ball in and power to one side. That is a bad switch right ?
Thanks for help !

 

[Lumpy Grits]

Yup-me thinks so.
There should be NO continuity(closed circuit)between the 2 terminals until the ball is depressed.
Just think of this as a momentary(normally 'open')switch. Shift'n to 'R' closes the switch.
LG

 

[firejeep]

Thanks will order replacement and update when it's in

Thanks

 

[Lumpy Grits]

Thanks will order replacement and update when it's in

Thanks

Order 2-
LG

 

[firejeep]

OK now I am confused. I just got the new switches and when i hold them and touch my leads from tester it beeps continuous, push the ball no beep.
Electrical is not my best. Need help. Thanks

 

[Lumpy Grits]

Install and see-
LG

 

[firejeep]

Nothing
I went from lights in 1-3, not in reverse. To no lights. I now have 3 switches, it seems when I plug them in and place them in the hole, no power.

 

[Lumpy Grits]

OK-Run a 'jumper' on the switch's plug between the 2 terminals(paper-clip).
Turn ign switch on-Put in "R". Do you have light?
LG

 

[BusaDave9]

You say there is no power. How are you checking? Do you have one lead on ground and then put the other on the switch? Or are you checking accross the switch? Do you have your meter set to continuity or voltage? Your meter should be set to continuity or ohms when the switch is disconnected. It should be set to volts when the circuit is live (key on and you are expecting the lights to be on)